Transocean (RIG) 10-Q 4 May 21 2021 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2021	Apr. 27, 2021
Document and Entity Information
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Mar. 31, 2021
Document Transition Report	false
Entity File Number	001-38373
Entity Registrant Name	Transocean Ltd
Entity Incorporation, State or Country Code	V8
Entity Tax Identification Number	98-0599916
Entity Address, Address Line One	Turmstrasse 30
Entity Address, City or Town	Steinhausen
Entity Address, Country	CH
Entity Address, Postal Zip Code	6312
City Area Code	+41 (41)
Local Phone Number	749-0500
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		617,298,955
Entity Central Index Key	0001451505
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	Q1
Amendment Flag	false
Shares
Document and Entity Information
Title of 12(b) Security	Shares
Trading Symbol	RIG
Security Exchange Name	NYSE
0.50% Exchangeable Senior Bonds due January 2023
Document and Entity Information
Title of 12(b) Security	0.50% Exchangeable Senior Bonds due 2023
Trading Symbol	RIG/23
Security Exchange Name	NYSE

CONDENSED CONSOLIDATED STATEMEN

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Operating revenues
Contract drilling revenues	$ 653	$ 759
Revenue from Contract with Customer, Product and Service [Extensible List]	us-gaap:OilAndGasServiceMember	us-gaap:OilAndGasServiceMember
Costs and expenses
Operating and maintenance	$ 435	$ 540
Cost, Product and Service [Extensible List]	us-gaap:OilAndGasServiceMember	us-gaap:OilAndGasServiceMember
Depreciation and amortization	$ 187	$ 206
General and administrative	39	43
Total costs and expenses	661	789
Loss on impairment		(168)
Lloss on disposal of assets, net	(59)	(1)
Operating loss	(67)	(199)
Other income (expense), net
Interest income	3	9
Interest expense, net of amounts capitalized	(115)	(160)
Gain (loss) on retirement of debt	51	(57)
Other, net	9	12
Total other income (expense), net	(52)	(196)
Loss before income tax expense	(119)	(395)
Income tax benefit	(21)	(4)
Net loss	(98)	(391)
Net income attributable to noncontrolling interest	1	1
Net loss attributable to controlling interest	$ (99)	$ (392)
Loss per share, basic and diluted (in dollars per share)	$ (0.16)	$ (0.64)
Weighted average shares, basic and diluted (in shares)	617	614

CONDENSED CONSOLIDATED STATEM_2

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS
Net loss	$ (98)	$ (391)
Net income attributable to noncontrolling interest	1	1
Net loss attributable to controlling interest	(99)	(392)
Components of net periodic benefit costs before reclassifications	(5)	(9)
Components of net periodic benefit costs reclassified to net loss	1	2
Other comprehensive loss before income taxes	(4)	(7)
Other comprehensive loss	(4)	(7)
Other comprehensive loss attributable to controlling interest	(4)	(7)
Total comprehensive loss	(102)	(398)
Total comprehensive income attributable to noncontrolling interest	1	1
Total comprehensive loss attributable to controlling interest	$ (103)	$ (399)

CONDENSED CONSOLIDATED BALANCE

CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
Assets
Cash and cash equivalents	$ 1,066	$ 1,154
Accounts receivable, net of allowance of $2 at March 31, 2021 and December 31, 2020	511	583
Materials and supplies, net of allowance of $144 and $143 at March 31, 2021 and December 31, 2020, respectively	433	434
Restricted cash and cash equivalents	388	406
Other current assets	161	163
Total current assets	2,559	2,740
Property and equipment	23,020	23,040
Less accumulated depreciation	(5,541)	(5,373)
Property and equipment, net	17,479	17,667
Contract intangible assets	337	393
Deferred income taxes, net	11	9
Other assets	974	995
Total assets	21,360	21,804
Liabilities and equity
Accounts payable	189	194
Accrued income taxes	29	28
Debt due within one year	524	505
Other current liabilities	561	659
Total current liabilities	1,303	1,386
Long-term debt	7,096	7,302
Deferred income taxes, net	319	315
Other long-term liabilities	1,302	1,366
Total long-term liabilities	8,717	8,983
Commitments and contingencies
Shares, CHF 0.10 par value, 824,650,668 authorized, 142,363,647 conditionally authorized, 639,676,165 issued and 617,288,705 outstanding at March 31, 2021, and 824,650,660 authorized, 142,363,647 conditionally authorized, 639,676,165 issued and 615,140,276 outstanding at December 31, 2020	60	60
Additional paid-in capital	13,508	13,501
Accumulated deficit	(1,965)	(1,866)
Accumulated other comprehensive loss	(267)	(263)
Total controlling interest shareholders' equity	11,336	11,432
Noncontrolling interest	4	3
Total equity	11,340	11,435
Total liabilities and equity	$ 21,360	$ 21,804

CONDENSED CONSOLIDATED BALANC_2

CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) $ in Millions	Mar. 31, 2021USD ($)shares	Mar. 31, 2021SFr / shares	Dec. 31, 2020USD ($)shares	Dec. 31, 2020SFr / shares
CONDENSED CONSOLIDATED BALANCE SHEETS
Allowance for doubtful accounts | $	$ 2		$ 2
Materials and supplies, net of allowance | $	$ 144		$ 143
Shares, CHF par value (in Swiss francs per share) | SFr / shares		SFr 0.10		SFr 0.10
Shares, authorized	824,650,668		824,650,660
Shares, conditionally authorized	142,363,647		142,363,647
Shares, issued	639,676,165		639,676,165
Shares, outstanding	617,288,705		615,140,276

CONDENSED CONSOLIDATED STATEM_3

CONDENSED CONSOLIDATED STATEMENTS OF EQUITY - USD ($) $ in Millions	Total controlling interest shareholders' equityPeriod of Adoption, Adjustment	Total controlling interest shareholders' equity	Shares	Additional paid-in capital	Accumulated deficitPeriod of Adoption, Adjustment	Accumulated deficit	Accumulated other comprehensive loss	Noncontrolling interest	Period of Adoption, Adjustment	Total
Balance at Dec. 31, 2019	$ (2)	$ 11,862	$ 59	$ 13,424	$ (2)	$ (1,297)	$ (324)	$ 5	$ (2)	$ 11,867
Increase (Decrease) in Shareholders' Equity
Share-based compensation		8		8						8
Issuance of shares under share-based compensation plans			1	(1)
Net loss attributable to controlling interest						(392)				(392)
Other comprehensive loss attributable to controlling interest							(7)			(7)
Total comprehensive loss attributable to controlling interest		(399)								(399)
Total comprehensive income attributable to noncontrolling interest								1
Total comprehensive loss										(398)
Balance at Mar. 31, 2020		11,469	60	13,431		(1,691)	(331)	6		11,475
Balance at Dec. 31, 2019	$ (2)	11,862	59	13,424	$ (2)	(1,297)	(324)	5	$ (2)	11,867
Balance at Dec. 31, 2020		11,432	60	13,501		(1,866)	(263)	3		11,435
Increase (Decrease) in Shareholders' Equity
Share-based compensation		7		7						7
Net loss attributable to controlling interest						(99)				(99)
Other comprehensive loss attributable to controlling interest							(4)			(4)
Total comprehensive loss attributable to controlling interest		(103)								(103)
Total comprehensive income attributable to noncontrolling interest								1
Total comprehensive loss										(102)
Balance at Mar. 31, 2021		$ 11,336	$ 60	$ 13,508		$ (1,965)	$ (267)	$ 4		$ 11,340

CONDENSED CONSOLIDATED STATEM_4

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Cash flows from operating activities
Net loss	$ (98)	$ (391)
Adjustments to reconcile to net cash provided by operating activities:
Contract intangible asset amortization	56	48
Depreciation and amortization	187	206
Share-based compensation expense	7	8
Loss on impairment		168
Loss on disposal of assets, net	59	1
(Gain) loss on retirement of debt	(51)	57
Deferred income tax expense	2	10
Other, net	7	18
Changes in deferred revenues, net	(37)	5
Changes in deferred costs, net	3	(11)
Changes in other operating assets and liabilities, net	(39)	(167)
Net cash provided by (used in) operating activities	96	(48)
Cash flows from investing activities
Capital expenditures	(59)	(107)
Proceeds from disposal of assets, net	6	1
Investments in unconsolidated affiliates		(6)
Net cash used in investing activities	(53)	(112)
Cash flows from financing activities
Proceeds from issuance of debt, net of issue costs		743
Repayments of debt	(139)	(909)
Other, net	(10)	(9)
Net cash used in financing activities	(149)	(175)
Net decrease in unrestricted and restricted cash and cash equivalents	(106)	(335)
Unrestricted and restricted cash and cash equivalents, beginning of period	1,560	2,349
Unrestricted and restricted cash and cash equivalents, end of period	$ 1,454	$ 2,014

Business

Business	3 Months Ended
	Mar. 31, 2021
Business
Business	Note 1—Business Transocean Ltd. (together with its subsidiaries and predecessors, unless the context requires otherwise, “Transocean,” “we,” “us” or “our”) is a leading international provider of offshore contract drilling services for oil and gas wells. We specialize in technically demanding sectors of the offshore drilling business with a particular focus on ultra-deepwater and harsh environment drilling services. Our mobile offshore drilling fleet is considered one of the most versatile fleets in the world. We contract our drilling rigs, related equipment and work crews predominantly on a dayrate basis to drill oil and gas wells. As of March 31, 2021, we owned or had partial ownership interests in and operated a fleet of 37 mobile offshore drilling units, including 27 ultra-deepwater floaters and 10 harsh environment floaters. As of March 31, 2021, we were constructing two ultra-deepwater drillships.

Significant Accounting Policies

Significant Accounting Policies	3 Months Ended
	Mar. 31, 2021
Significant Accounting Policies
Significant Accounting Policies	Note 2—Significant Accounting Policies Presentation Form 10-K filed on March 1, 2021 Accounting estimates Fair value measurements

Accounting Standards Update

Accounting Standards Update	3 Months Ended
	Mar. 31, 2021
Accounting Standards Update
Accounting Standards Update	Note 3—Accounting Standards Update Recently adopted accounting standards Debt with conversion and other options Note 7—Debt

Unconsolidated Affiliates

Unconsolidated Affiliates	3 Months Ended
	Mar. 31, 2021
Unconsolidated Affiliates
Unconsolidated Affiliates	Note 4—Unconsolidated Affiliates Equity investments Transocean Norge . Orion, our most significant equity investment, and in the three months ending June 30, 2021, we expect to make an additional $33 million cash contribution to Orion. At March 31, 2021 and December 31, 2020, the aggregate carrying amount of our equity investments was $139 million and $138 million, respectively, recorded in other assets, of which the aggregate carrying amount of our equity investment in Orion was $105 million and $104 million, respectively.

Revenues

Revenues	3 Months Ended
	Mar. 31, 2021
Revenues
Revenues	Note 5—Revenues Overview Disaggregation ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three months ended March 31, 2021 ​ ​ Three months ended March 31, 2020 ​ ​ U.S. Norway Other Total U.S. Norway Other Total Ultra-deepwater floaters $ 266 ​ $ — ​ $ 170 ​ $ 436 $ 287 ​ $ — ​ $ 241 ​ $ 528 Harsh environment floaters ​ ​ 4 ​ ​ 202 ​ ​ 11 ​ ​ 217 ​ ​ ​ — ​ ​ 207 ​ ​ 13 ​ ​ 220 ​ Midwater floaters ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ ​ — ​ ​ — ​ ​ 11 ​ ​ 11 ​ Total contract drilling revenues $ 270 ​ $ 202 ​ $ 181 ​ $ 653 $ 287 ​ $ 207 ​ $ 265 ​ $ 759 ​ Contract liabilities ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, ​ December 31, ​ ​ 2021 2020 Deferred contract revenues, recorded in other current liabilities $ 115 ​ $ 133 ​ Deferred contract revenues, recorded in other long-term liabilities ​ ​ 304 ​ ​ 323 ​ Total contract liabilities $ 419 ​ $ 456 ​ Significant changes in contract liabilities were as follows (in millions): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three months ended ​ ​ ​ March 31, ​ ​ 2021 2020 Total contract liabilities, beginning of period ​ $ 456 ​ $ 529 ​ Decrease due to recognition of revenues for goods and services ​ ​ (44) ​ ​ (41) ​ Increase due to goods and services transferred over time ​ ​ 7 ​ ​ 46 ​ Total contract liabilities, end of period ​ $ 419 ​ $ 534 ​ ​

Drilling Fleet

Drilling Fleet	3 Months Ended
	Mar. 31, 2021
Drilling Fleet
Drilling Fleet	Note 6—Drilling Fleet Construction work in progress ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three months ended ​ ​ ​ March 31, ​ ​ 2021 2020 Construction work in progress, beginning of period $ 828 ​ $ 753 ​ ​ ​ ​ ​ ​ ​ ​ ​ Capital expenditures ​ ​ ​ ​ ​ ​ ​ Newbuild construction program ​ ​ 45 ​ ​ 50 ​ Other equipment and construction projects ​ ​ 14 ​ ​ 57 ​ Total capital expenditures ​ ​ 59 ​ ​ 107 ​ Changes in accrued capital additions ​ ​ (7) ​ ​ (24) ​ ​ ​ ​ ​ ​ ​ ​ ​ Property and equipment placed into service ​ ​ (14) ​ ​ (62) ​ Construction work in progress, end of period $ 866 ​ $ 774 ​ ​ Impairments of assets held and used received for the assets in the principal or most advantageous markets for the assets in an orderly transaction between participants as of the measurement date. Our estimate of fair value required us to use significant other observable inputs, representative of Level 2 fair value measurements, including the marketability of the rig and prices of comparable rigs that may be sold for scrap value. Impairments of assets held for sale Polar Pioneer Songa Dee Sedco 711 Sedco 714, Dispositions Leiv Eiriksson

Debt

Debt	3 Months Ended
	Mar. 31, 2021
Debt
Debt	Note 7—Debt Overview Outstanding debt ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Principal amount ​ ​ Carrying amount ​ ​ March 31, ​ December 31, ​ March 31, ​ December 31, ​ ​ 2021 2020 2021 2020 6.375% Senior Notes due December 2021 ​ $ 38 ​ $ 38 ​ ​ $ 38 ​ $ 38 ​ 5.52% Senior Secured Notes due May 2022 ​ ​ 89 ​ ​ 111 ​ ​ ​ 88 ​ ​ 111 ​ 3.80% Senior Notes due October 2022 ​ ​ 27 ​ ​ 27 ​ ​ ​ 27 ​ ​ 27 ​ 0.50% Exchangeable Senior Bonds due January 2023 ​ ​ 140 ​ ​ 463 ​ ​ ​ 139 ​ ​ 462 ​ 5.375% Senior Secured Notes due May 2023 ​ ​ 362 ​ ​ 364 ​ ​ ​ 359 ​ ​ 360 ​ 5.875% Senior Secured Notes due January 2024 ​ ​ 544 ​ ​ 585 ​ ​ ​ 536 ​ ​ 577 ​ 7.75% Senior Secured Notes due October 2024 ​ ​ 360 ​ ​ 360 ​ ​ ​ 354 ​ ​ 354 ​ 6.25% Senior Secured Notes due December 2024 ​ ​ 375 ​ ​ 375 ​ ​ ​ 370 ​ ​ 369 ​ 6.125% Senior Secured Notes due August 2025 ​ ​ 435 ​ ​ 468 ​ ​ ​ 428 ​ ​ 461 ​ 7.25% Senior Notes due November 2025 ​ ​ 411 ​ ​ 411 ​ ​ ​ 406 ​ ​ 405 ​ 4.00% Senior Guaranteed Exchangeable Bonds due December 2025 ​ ​ 294 ​ ​ — ​ ​ ​ 260 ​ ​ — ​ 7.50% Senior Notes due January 2026 ​ ​ 569 ​ ​ 569 ​ ​ ​ 565 ​ ​ 565 ​ 2.50% Senior Guaranteed Exchangeable Bonds due January 2027 ​ ​ 238 ​ ​ 238 ​ ​ ​ 274 ​ ​ 277 ​ 11.50% Senior Guaranteed Notes due January 2027 ​ ​ 687 ​ ​ 687 ​ ​ ​ 1,113 ​ ​ 1,139 ​ 6.875% Senior Secured Notes due February 2027 ​ ​ 550 ​ ​ 550 ​ ​ ​ 543 ​ ​ 542 ​ 8.00% Senior Notes due February 2027 ​ ​ 612 ​ ​ 612 ​ ​ ​ 607 ​ ​ 606 ​ 7.45% Notes due April 2027 ​ ​ 52 ​ ​ 52 ​ ​ ​ 51 ​ ​ 51 ​ 8.00% Debentures due April 2027 ​ ​ 22 ​ ​ 22 ​ ​ ​ 22 ​ ​ 22 ​ 7.00% Notes due June 2028 ​ ​ 261 ​ ​ 261 ​ ​ ​ 265 ​ ​ 266 ​ 7.50% Notes due April 2031 ​ ​ 396 ​ ​ 396 ​ ​ ​ 394 ​ ​ 394 ​ 6.80% Senior Notes due March 2038 ​ ​ 610 ​ ​ 610 ​ ​ ​ 605 ​ ​ 605 ​ 7.35% Senior Notes due December 2041 ​ ​ 177 ​ ​ 177 ​ ​ ​ 176 ​ ​ 176 ​ Total debt ​ ​ 7,249 ​ ​ 7,376 ​ ​ ​ 7,620 ​ ​ 7,807 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Less debt due within one year ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 6.375% Senior Notes due December 2021 ​ ​ 38 ​ ​ 38 ​ ​ ​ 38 ​ ​ 38 ​ 5.52% Senior Secured Notes due May 2022 ​ ​ 71 ​ ​ 93 ​ ​ ​ 70 ​ ​ 92 ​ 5.375% Senior Secured Notes due May 2023 ​ ​ 47 ​ ​ 47 ​ ​ ​ 46 ​ ​ 46 ​ 5.875% Senior Secured Notes due January 2024 ​ ​ 83 ​ ​ 83 ​ ​ ​ 80 ​ ​ 80 ​ 7.75% Senior Secured Notes due October 2024 ​ ​ 60 ​ ​ 60 ​ ​ ​ 58 ​ ​ 58 ​ 6.25% Senior Secured Notes due December 2024 ​ ​ 62 ​ ​ 62 ​ ​ ​ 60 ​ ​ 60 ​ 6.125% Senior Secured Notes due August 2025 ​ ​ 66 ​ ​ 66 ​ ​ ​ 64 ​ ​ 64 ​ 2.50% Senior Guaranteed Exchangeable Bonds due January 2027 ​ ​ — ​ ​ — ​ ​ ​ 6 ​ ​ 6 ​ 11.50% Senior Guaranteed Notes due January 2027 ​ ​ — ​ ​ — ​ ​ ​ 70 ​ ​ 61 ​ 6.875% Senior Secured Notes due February 2027 ​ ​ 34 ​ ​ — ​ ​ ​ 32 ​ ​ — ​ Total debt due within one year ​ ​ 461 ​ ​ 449 ​ ​ ​ 524 ​ ​ 505 ​ Total long-term debt ​ $ 6,788 ​ $ 6,927 ​ $ 7,096 ​ $ 7,302 ​ ​ Scheduled maturities ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Principal Other ​ ​ installments installments Total Twelve months ending March 31, ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 2022 ​ $ 461 ​ $ 76 ​ $ 537 ​ 2023 ​ ​ 588 ​ ​ 76 ​ ​ 664 ​ 2024 ​ ​ 895 ​ ​ 77 ​ ​ 972 ​ 2025 ​ ​ 516 ​ ​ 77 ​ ​ 593 ​ 2026 ​ ​ 1,527 ​ ​ 78 ​ ​ 1,605 ​ Thereafter ​ ​ 3,262 ​ ​ 78 ​ ​ 3,340 ​ Total installments of debt ​ $ 7,249 ​ $ 462 ​ ​ 7,711 ​ Total debt-related balances, net ​ ​ ​ ​ ​ ​ ​ ​ (91) ​ Total carrying amount of debt ​ ​ ​ ​ ​ ​ ​ $ 7,620 ​ ​ Interest rate adjustments Secured Credit Facility Note 10—Contingencies Exchangeable bonds Exchange terms ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Implied ​ ​ Exchange exchange ​ rate price 0.50% Exchangeable Senior Bonds due January 2023 ​ ​ 97.29756 ​ $ 10.28 ​ 4.00% Senior Guaranteed Exchangeable Bonds due December 2025 ​ ​ 190.47620 ​ ​ 5.25 ​ 2.50% Senior Guaranteed Exchangeable Bonds due January 2027 ​ ​ 162.16260 ​ ​ 6.17 ​ ​ The exchange rates of our exchangeable bonds, identified above, are subject to adjustment upon the occurrence of certain events. The 0.50% Exchangeable Senior Bonds may be exchanged by holders into Transocean Ltd. shares at any time prior to the close of business on the business day immediately preceding the maturity date. The 2.50% Senior Guaranteed Exchangeable Bonds may be exchanged by holders into Transocean Ltd. shares at any time prior to the close of business on the second business day immediately preceding the maturity date or redemption date. The 4.00% Senior Guaranteed Exchangeable Bonds may be exchanged by holders at any time prior to the close of business on the second business day immediately preceding the maturity date and, at our election, such exchange may be settled by delivering cash, Transocean Ltd. shares or a combination of cash and shares. Effective interest rates and fair values ​ ​ ​ ​ ​ ​ ​ ​ ​ Effective Fair ​ interest rate value 0.50% Exchangeable Senior Bonds due January 2023 ​ ​ 0.5% ​ $ 104 ​ 4.00% Senior Guaranteed Exchangeable Bonds due December 2025 ​ ​ 6.9% ​ ​ 280 ​ 2.50% Senior Guaranteed Exchangeable Bonds due January 2027 ​ ​ 0.0% ​ ​ 195 ​ ​ We estimated the fair values of the exchangeable debt instruments, including the exchange features, by employing a binomial lattice model and by using significant other observable inputs, representative of a Level 2 fair value measurement, including the terms and credit spreads of our debt and expected volatility of the market price for our shares. Related balances Debt issuances Senior guaranteed exchangeable bonds Debt retirements Guaranteed senior unsecured notes Debt retirements During the three months ended March 31, 2021 and 2020, we retired certain notes as a result of redemption, private exchanges and open market repurchases. The aggregate principal amounts, cash payments and recognized gain or loss for such transactions were as follows (in millions): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three months ended March 31, 2021 ​ Three months ended March 31, 2020 ​ ​ Exchanged Repurchased Total Redeemed Repurchased Total ​ 6.50% Senior Notes due November 2020 ​ $ — ​ $ — ​ $ — ​ $ — ​ $ 8 ​ $ 8 ​ 6.375% Senior Notes due December 2021 ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ 38 ​ ​ 38 ​ 3.80% Senior Notes due October 2022 ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ 3 ​ ​ 3 ​ 0.50% Exchangeable Senior Bonds due January 2023 ​ ​ 323 ​ ​ — ​ ​ 323 ​ ​ — ​ ​ — ​ ​ — ​ 5.375% Senior Secured Notes due May 2023 ​ ​ — ​ ​ 1 ​ ​ 1 ​ ​ — ​ ​ 6 ​ ​ 6 ​ 9.00% Senior Notes due July 2023 ​ ​ — ​ ​ — ​ ​ — ​ ​ 714 ​ ​ — ​ ​ 714 ​ Aggregate principal amount retired ​ $ 323 ​ $ 1 ​ $ 324 ​ $ 714 ​ $ 55 ​ $ 769 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Aggregate cash payment ​ $ 11 ​ $ 1 ​ $ 12 ​ $ 767 ​ $ 46 ​ $ 813 ​ Aggregate principal amount of debt issued in exchanges ​ $ 294 ​ $ — ​ $ 294 ​ $ — ​ $ — ​ $ — ​ Aggregate net gain (loss) ​ $ 51 ​ $ — ​ $ 51 ​ $ (65) ​ $ 8 ​ $ (57) ​ ​

Income Taxes

Income Taxes	3 Months Ended
	Mar. 31, 2021
Income Taxes
Income Taxes	Note 8—Income Taxes Tax provision and rate Tax returns Brazil tax investigations aggregate tax assessment, including interest and penalties, was for corporate income tax of BRL 641 million, equivalent to approximately $114 million, and indirect tax of BRL 96 million, equivalent to $17 million. We believe our returns are materially correct as filed, and we are vigorously contesting these assessments. An unfavorable outcome on these proposed assessments could have a material adverse effect on our condensed consolidated statement of financial position, results of operations or cash flows. Other tax matters

Loss Per Share

Loss Per Share	3 Months Ended
	Mar. 31, 2021
Loss Per Share
Loss Per Share	Note 9—Loss Per Share The computation of basic and diluted loss per share were as follows (in millions, except per share data): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three months ended ​ ​ ​ March 31, ​ ​ ​ 2021 ​ 2020 ​ Numerator for loss per share, basic and diluted ​ ​ ​ ​ ​ ​ ​ Net loss attributable to controlling interest ​ $ (99) ​ $ (392) ​ ​ ​ ​ ​ ​ ​ ​ ​ Denominator for loss per share, basic and diluted ​ ​ ​ ​ ​ ​ ​ Weighted-average shares outstanding ​ ​ 616 ​ ​ 613 ​ Effect of share-based awards ​ ​ 1 ​ ​ 1 ​ Weighted-average shares for per share calculation ​ ​ 617 ​ ​ 614 ​ ​ ​ ​ ​ ​ ​ ​ ​ Loss per share, basic and diluted ​ $ (0.16) ​ $ (0.64) ​ ​ In the three months ended March 31, 2021 and 2020, we excluded from the calculation 13.8 million and 11.1 million shares issuable, respectively, pursuant to share-based awards since the effect would have been antidilutive. In the three months ended March 31, 2021 and 2020, we excluded from the calculation 92.9 million and 84.0 million shares issuable, respectively, upon exchange of the 0.50% Exchangeable Senior Bonds, the 2.50% Senior Guaranteed Exchangeable Bonds and the 4.00% Senior Guaranteed Exchangeable Bonds since the effect would have been antidilutive.

Contingencies

Contingencies	3 Months Ended
	Mar. 31, 2021
Contingencies
Contingencies	Note 10—Contingencies Legal proceedings Debt exchange litigation and purported notice of default— On September 23, 2020, we filed an answer to the Claim with the Court and asserted counterclaims seeking a declaratory judgment that, among other matters, the Internal Reorganization did not cause a default under the indenture governing the 8.00% Senior Notes. Concurrently, with our answer and counterclaims, we also submitted a motion for summary judgment seeking an expedited judgment on our request for declaratory judgment. Whitebox subsequently submitted a cross motion for summary judgment seeking dismissal of our counterclaims. On November 30, 2020, while awaiting the Court’s ruling on our motion for summary judgment, we amended certain of our financing documents and implemented certain internal reorganization transactions, which resolved the allegations contained in the purported notices of default. On December 17, 2020, the Court issued its ruling granting our motion for summary judgment and denying the plaintiff’s cross motion for summary judgment, holding, among other matters, that the allegations contained in the purported notice of default did not constitute a default under the indenture governing the 8.00% Senior Notes. Whitebox has appealed the Court’s ruling. The facts alleged in the purported notice of default under the 8.00% Senior Notes were the same as the facts underlying the Claim and the purported notice of default under the 7.25% Senior Notes. Accordingly, following the amendment and internal reorganization transactions on November 30, 2020, and the subsequent ruling from the Court granting our motion for summary judgment, we do not expect the liability, if any, resulting from these matters to have a material adverse effect on our condensed consolidated statement of financial position, results of operations or cash flows. Asbestos litigation One of our subsidiaries has been named as a defendant, along with numerous other companies, in lawsuits arising out of the subsidiary’s manufacture and sale of heat exchangers, and involvement in the construction and refurbishment of major industrial complexes alleging bodily injury or personal injury as a result of exposure to asbestos. As of March 31, 2021, the subsidiary was a defendant in approximately 256 lawsuits with a corresponding number of plaintiffs. For many of these lawsuits, we have not been provided sufficient information from the plaintiffs to determine whether all or some of the plaintiffs have claims against the subsidiary, the basis of any such claims, or the nature of their alleged injuries. The operating assets of the subsidiary were sold in 1989. In September 2018, the subsidiary and certain insurers agreed to a settlement of outstanding disputes that provided the subsidiary with cash and an annuity. Together with a coverage-in-place agreement with certain insurers and additional coverage issued by other insurers, we believe the subsidiary has sufficient resources to respond to both the current lawsuits as well as future lawsuits of a similar nature. While we cannot predict or provide assurance as to the outcome of these matters, we do not expect the ultimate liability, if any, resulting from these claims to have a material adverse effect on our condensed consolidated statement of financial position, results of operations or cash flows. Other matters Environmental matters We have certain potential liabilities under the Comprehensive Environmental Response, Compensation, and Liability Act (“CERCLA”) and similar state acts regulating cleanup of hazardous substances at various waste disposal sites, including those described below. CERCLA is intended to expedite the remediation of hazardous substances without regard to fault. Potentially responsible parties (“PRPs”) for each site include present and former owners and operators of, transporters to and generators of the substances at the site. It is difficult to quantify the potential cost of environmental matters and remediation obligations. Liability is strict and can be joint and several. One of our subsidiaries was named as a PRP in connection with a site located in Santa Fe Springs, California, known as the Waste Disposal, Inc. site. We and other PRPs agreed, under a participation agreement with the U.S. Environmental Protection Agency (the “EPA”) and the U.S. Department of Justice, to settle our potential liabilities by remediating the site. The remedial action for the site was completed in 2006. Our share of the ongoing operating and maintenance costs has been insignificant, and we do not expect any additional potential liabilities to be material. Resolutions of other claims by the EPA, the involved state agency or PRPs are at various stages of investigation. Nevertheless, based on available information, we do not expect the ultimate liability, if any, resulting from all environmental matters and known potential legal claims that are likely to be asserted, to have a material adverse effect on our condensed consolidated statement of financial position, results of operations or cash flows.

Financial Instruments

Financial Instruments	3 Months Ended
	Mar. 31, 2021
Financial Instruments
Financial Instruments	Note 11—Financial Instruments Overview ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, 2021 ​ December 31, 2020 ​ ​ Carrying ​ Fair ​ Carrying ​ Fair ​ amount value amount value Cash and cash equivalents $ 1,066 ​ $ 1,066 ​ $ 1,154 ​ $ 1,154 ​ Restricted cash and cash equivalents ​ ​ 388 ​ ​ 388 ​ ​ 406 ​ ​ 406 ​ Long-term debt, including current maturities ​ ​ 7,620 ​ ​ 5,503 ​ ​ 7,807 ​ ​ 4,820 ​ ​ Cash and cash equivalents Restricted cash and cash equivalents Long-term debt, including current maturities Note 7—Debt

Significant Accounting Polici_2

Significant Accounting Policies (Policies)	3 Months Ended
	Mar. 31, 2021
Significant Accounting Policies
Presentation	Presentation Form 10-K filed on March 1, 2021
Accounting estimates	Accounting estimates
Fair value measurements	Fair value measurements

Revenues (Tables)

Revenues (Tables)	3 Months Ended
	Mar. 31, 2021
Revenues
Schedule of revenue disaggregation	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three months ended March 31, 2021 ​ ​ Three months ended March 31, 2020 ​ ​ U.S. Norway Other Total U.S. Norway Other Total Ultra-deepwater floaters $ 266 ​ $ — ​ $ 170 ​ $ 436 $ 287 ​ $ — ​ $ 241 ​ $ 528 Harsh environment floaters ​ ​ 4 ​ ​ 202 ​ ​ 11 ​ ​ 217 ​ ​ ​ — ​ ​ 207 ​ ​ 13 ​ ​ 220 ​ Midwater floaters ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ ​ — ​ ​ — ​ ​ 11 ​ ​ 11 ​ Total contract drilling revenues $ 270 ​ $ 202 ​ $ 181 ​ $ 653 $ 287 ​ $ 207 ​ $ 265 ​ $ 759
Schedule of contract balances and changes	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, ​ December 31, ​ ​ 2021 2020 Deferred contract revenues, recorded in other current liabilities $ 115 ​ $ 133 ​ Deferred contract revenues, recorded in other long-term liabilities ​ ​ 304 ​ ​ 323 ​ Total contract liabilities $ 419 ​ $ 456 ​ Significant changes in contract liabilities were as follows (in millions): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three months ended ​ ​ ​ March 31, ​ ​ 2021 2020 Total contract liabilities, beginning of period ​ $ 456 ​ $ 529 ​ Decrease due to recognition of revenues for goods and services ​ ​ (44) ​ ​ (41) ​ Increase due to goods and services transferred over time ​ ​ 7 ​ ​ 46 ​ Total contract liabilities, end of period ​ $ 419 ​ $ 534 ​

Drilling Fleet (Tables)

Drilling Fleet (Tables)	3 Months Ended
	Mar. 31, 2021
Drilling Fleet
Changes in our construction work in progress, including capital expenditures and capitalized interest	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three months ended ​ ​ ​ March 31, ​ ​ 2021 2020 Construction work in progress, beginning of period $ 828 ​ $ 753 ​ ​ ​ ​ ​ ​ ​ ​ ​ Capital expenditures ​ ​ ​ ​ ​ ​ ​ Newbuild construction program ​ ​ 45 ​ ​ 50 ​ Other equipment and construction projects ​ ​ 14 ​ ​ 57 ​ Total capital expenditures ​ ​ 59 ​ ​ 107 ​ Changes in accrued capital additions ​ ​ (7) ​ ​ (24) ​ ​ ​ ​ ​ ​ ​ ​ ​ Property and equipment placed into service ​ ​ (14) ​ ​ (62) ​ Construction work in progress, end of period $ 866 ​ $ 774 ​

Debt (Tables)

Debt (Tables)	3 Months Ended
	Mar. 31, 2021
Schedule of debt	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Principal amount ​ ​ Carrying amount ​ ​ March 31, ​ December 31, ​ March 31, ​ December 31, ​ ​ 2021 2020 2021 2020 6.375% Senior Notes due December 2021 ​ $ 38 ​ $ 38 ​ ​ $ 38 ​ $ 38 ​ 5.52% Senior Secured Notes due May 2022 ​ ​ 89 ​ ​ 111 ​ ​ ​ 88 ​ ​ 111 ​ 3.80% Senior Notes due October 2022 ​ ​ 27 ​ ​ 27 ​ ​ ​ 27 ​ ​ 27 ​ 0.50% Exchangeable Senior Bonds due January 2023 ​ ​ 140 ​ ​ 463 ​ ​ ​ 139 ​ ​ 462 ​ 5.375% Senior Secured Notes due May 2023 ​ ​ 362 ​ ​ 364 ​ ​ ​ 359 ​ ​ 360 ​ 5.875% Senior Secured Notes due January 2024 ​ ​ 544 ​ ​ 585 ​ ​ ​ 536 ​ ​ 577 ​ 7.75% Senior Secured Notes due October 2024 ​ ​ 360 ​ ​ 360 ​ ​ ​ 354 ​ ​ 354 ​ 6.25% Senior Secured Notes due December 2024 ​ ​ 375 ​ ​ 375 ​ ​ ​ 370 ​ ​ 369 ​ 6.125% Senior Secured Notes due August 2025 ​ ​ 435 ​ ​ 468 ​ ​ ​ 428 ​ ​ 461 ​ 7.25% Senior Notes due November 2025 ​ ​ 411 ​ ​ 411 ​ ​ ​ 406 ​ ​ 405 ​ 4.00% Senior Guaranteed Exchangeable Bonds due December 2025 ​ ​ 294 ​ ​ — ​ ​ ​ 260 ​ ​ — ​ 7.50% Senior Notes due January 2026 ​ ​ 569 ​ ​ 569 ​ ​ ​ 565 ​ ​ 565 ​ 2.50% Senior Guaranteed Exchangeable Bonds due January 2027 ​ ​ 238 ​ ​ 238 ​ ​ ​ 274 ​ ​ 277 ​ 11.50% Senior Guaranteed Notes due January 2027 ​ ​ 687 ​ ​ 687 ​ ​ ​ 1,113 ​ ​ 1,139 ​ 6.875% Senior Secured Notes due February 2027 ​ ​ 550 ​ ​ 550 ​ ​ ​ 543 ​ ​ 542 ​ 8.00% Senior Notes due February 2027 ​ ​ 612 ​ ​ 612 ​ ​ ​ 607 ​ ​ 606 ​ 7.45% Notes due April 2027 ​ ​ 52 ​ ​ 52 ​ ​ ​ 51 ​ ​ 51 ​ 8.00% Debentures due April 2027 ​ ​ 22 ​ ​ 22 ​ ​ ​ 22 ​ ​ 22 ​ 7.00% Notes due June 2028 ​ ​ 261 ​ ​ 261 ​ ​ ​ 265 ​ ​ 266 ​ 7.50% Notes due April 2031 ​ ​ 396 ​ ​ 396 ​ ​ ​ 394 ​ ​ 394 ​ 6.80% Senior Notes due March 2038 ​ ​ 610 ​ ​ 610 ​ ​ ​ 605 ​ ​ 605 ​ 7.35% Senior Notes due December 2041 ​ ​ 177 ​ ​ 177 ​ ​ ​ 176 ​ ​ 176 ​ Total debt ​ ​ 7,249 ​ ​ 7,376 ​ ​ ​ 7,620 ​ ​ 7,807 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Less debt due within one year ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 6.375% Senior Notes due December 2021 ​ ​ 38 ​ ​ 38 ​ ​ ​ 38 ​ ​ 38 ​ 5.52% Senior Secured Notes due May 2022 ​ ​ 71 ​ ​ 93 ​ ​ ​ 70 ​ ​ 92 ​ 5.375% Senior Secured Notes due May 2023 ​ ​ 47 ​ ​ 47 ​ ​ ​ 46 ​ ​ 46 ​ 5.875% Senior Secured Notes due January 2024 ​ ​ 83 ​ ​ 83 ​ ​ ​ 80 ​ ​ 80 ​ 7.75% Senior Secured Notes due October 2024 ​ ​ 60 ​ ​ 60 ​ ​ ​ 58 ​ ​ 58 ​ 6.25% Senior Secured Notes due December 2024 ​ ​ 62 ​ ​ 62 ​ ​ ​ 60 ​ ​ 60 ​ 6.125% Senior Secured Notes due August 2025 ​ ​ 66 ​ ​ 66 ​ ​ ​ 64 ​ ​ 64 ​ 2.50% Senior Guaranteed Exchangeable Bonds due January 2027 ​ ​ — ​ ​ — ​ ​ ​ 6 ​ ​ 6 ​ 11.50% Senior Guaranteed Notes due January 2027 ​ ​ — ​ ​ — ​ ​ ​ 70 ​ ​ 61 ​ 6.875% Senior Secured Notes due February 2027 ​ ​ 34 ​ ​ — ​ ​ ​ 32 ​ ​ — ​ Total debt due within one year ​ ​ 461 ​ ​ 449 ​ ​ ​ 524 ​ ​ 505 ​ Total long-term debt ​ $ 6,788 ​ $ 6,927 ​ $ 7,096 ​ $ 7,302 ​
Scheduled maturities of debt	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Principal Other ​ ​ installments installments Total Twelve months ending March 31, ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 2022 ​ $ 461 ​ $ 76 ​ $ 537 ​ 2023 ​ ​ 588 ​ ​ 76 ​ ​ 664 ​ 2024 ​ ​ 895 ​ ​ 77 ​ ​ 972 ​ 2025 ​ ​ 516 ​ ​ 77 ​ ​ 593 ​ 2026 ​ ​ 1,527 ​ ​ 78 ​ ​ 1,605 ​ Thereafter ​ ​ 3,262 ​ ​ 78 ​ ​ 3,340 ​ Total installments of debt ​ $ 7,249 ​ $ 462 ​ ​ 7,711 ​ Total debt-related balances, net ​ ​ ​ ​ ​ ​ ​ ​ (91) ​ Total carrying amount of debt ​ ​ ​ ​ ​ ​ ​ $ 7,620 ​
Schedule of debt retirements	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three months ended March 31, 2021 ​ Three months ended March 31, 2020 ​ ​ Exchanged Repurchased Total Redeemed Repurchased Total ​ 6.50% Senior Notes due November 2020 ​ $ — ​ $ — ​ $ — ​ $ — ​ $ 8 ​ $ 8 ​ 6.375% Senior Notes due December 2021 ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ 38 ​ ​ 38 ​ 3.80% Senior Notes due October 2022 ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ 3 ​ ​ 3 ​ 0.50% Exchangeable Senior Bonds due January 2023 ​ ​ 323 ​ ​ — ​ ​ 323 ​ ​ — ​ ​ — ​ ​ — ​ 5.375% Senior Secured Notes due May 2023 ​ ​ — ​ ​ 1 ​ ​ 1 ​ ​ — ​ ​ 6 ​ ​ 6 ​ 9.00% Senior Notes due July 2023 ​ ​ — ​ ​ — ​ ​ — ​ ​ 714 ​ ​ — ​ ​ 714 ​ Aggregate principal amount retired ​ $ 323 ​ $ 1 ​ $ 324 ​ $ 714 ​ $ 55 ​ $ 769 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Aggregate cash payment ​ $ 11 ​ $ 1 ​ $ 12 ​ $ 767 ​ $ 46 ​ $ 813 ​ Aggregate principal amount of debt issued in exchanges ​ $ 294 ​ $ — ​ $ 294 ​ $ — ​ $ — ​ $ — ​ Aggregate net gain (loss) ​ $ 51 ​ $ — ​ $ 51 ​ $ (65) ​ $ 8 ​ $ (57) ​
Exchanged
Schedule of debt	Exchange terms ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Implied ​ ​ Exchange exchange ​ rate price 0.50% Exchangeable Senior Bonds due January 2023 ​ ​ 97.29756 ​ $ 10.28 ​ 4.00% Senior Guaranteed Exchangeable Bonds due December 2025 ​ ​ 190.47620 ​ ​ 5.25 ​ 2.50% Senior Guaranteed Exchangeable Bonds due January 2027 ​ ​ 162.16260 ​ ​ 6.17 ​ Effective interest rates and fair values ​ ​ ​ ​ ​ ​ ​ ​ ​ Effective Fair ​ interest rate value 0.50% Exchangeable Senior Bonds due January 2023 ​ ​ 0.5% ​ $ 104 ​ 4.00% Senior Guaranteed Exchangeable Bonds due December 2025 ​ ​ 6.9% ​ ​ 280 ​ 2.50% Senior Guaranteed Exchangeable Bonds due January 2027 ​ ​ 0.0% ​ ​ 195 ​

Loss Per Share (Tables)

Loss Per Share (Tables)	3 Months Ended
	Mar. 31, 2021
Loss Per Share
Loss Per Share	The computation of basic and diluted loss per share were as follows (in millions, except per share data): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three months ended ​ ​ ​ March 31, ​ ​ ​ 2021 ​ 2020 ​ Numerator for loss per share, basic and diluted ​ ​ ​ ​ ​ ​ ​ Net loss attributable to controlling interest ​ $ (99) ​ $ (392) ​ ​ ​ ​ ​ ​ ​ ​ ​ Denominator for loss per share, basic and diluted ​ ​ ​ ​ ​ ​ ​ Weighted-average shares outstanding ​ ​ 616 ​ ​ 613 ​ Effect of share-based awards ​ ​ 1 ​ ​ 1 ​ Weighted-average shares for per share calculation ​ ​ 617 ​ ​ 614 ​ ​ ​ ​ ​ ​ ​ ​ ​ Loss per share, basic and diluted ​ $ (0.16) ​ $ (0.64) ​

Financial Instruments (Tables)

Financial Instruments (Tables)	3 Months Ended
	Mar. 31, 2021
Financial Instruments
Carrying amounts and fair values of the financial instruments	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, 2021 ​ December 31, 2020 ​ ​ Carrying ​ Fair ​ Carrying ​ Fair ​ amount value amount value Cash and cash equivalents $ 1,066 ​ $ 1,066 ​ $ 1,154 ​ $ 1,154 ​ Restricted cash and cash equivalents ​ ​ 388 ​ ​ 388 ​ ​ 406 ​ ​ 406 ​ Long-term debt, including current maturities ​ ​ 7,620 ​ ​ 5,503 ​ ​ 7,807 ​ ​ 4,820 ​

Business (Details)

Business (Details)	Mar. 31, 2021item
Number of mobile offshore drilling units	37
Ultra-deepwater floaters
Number of mobile offshore drilling units	27
Number of mobile offshore drilling units under construction	2
Harsh environment floaters
Number of mobile offshore drilling units	10

Unconsolidated Affiliates (Deta

Unconsolidated Affiliates (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Investments
Investment in unconsolidated affiliate		$ 6
Aggregate carrying amount of equity investment	$ 139		$ 138
Transocean Norge
Investments
Ownership percentage	33.00%
Investment in unconsolidated affiliate		$ 6
Aggregate carrying amount of equity investment	$ 105		$ 104
Payment Three | Transocean Norge
Investments
Investment in unconsolidated affiliate	$ 33

Revenues (Disaggregation) (Deta

Revenues (Disaggregation) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Revenue
Recognized pre-operating costs	$ 14	$ 9
Unrecognized pre-operating costs	14		$ 20
Contract drilling revenues	653	759
Ultra-deepwater floaters
Revenue
Contract drilling revenues	436	528
Harsh environment floaters
Revenue
Contract drilling revenues	217	220
Midwater floaters
Revenue
Contract drilling revenues		11
U.S.
Revenue
Contract drilling revenues	270	287
U.S. | Ultra-deepwater floaters
Revenue
Contract drilling revenues	266	287
U.S. | Harsh environment floaters
Revenue
Contract drilling revenues	4
Norway
Revenue
Contract drilling revenues	202	207
Norway | Harsh environment floaters
Revenue
Contract drilling revenues	202	207
Other
Revenue
Contract drilling revenues	181	265
Other | Ultra-deepwater floaters
Revenue
Contract drilling revenues	170	241
Other | Harsh environment floaters
Revenue
Contract drilling revenues	$ 11	13
Other | Midwater floaters
Revenue
Contract drilling revenues		$ 11

Revenues (Contract liabilities)

Revenues (Contract liabilities) (Details) - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020	Mar. 31, 2020	Dec. 31, 2019
Contract balances
Deferred contract revenues, recorded in other current liabilities	$ 115	$ 133
Deferred contract revenues, recorded in other long-term liabilities	304	323
Total contract liabilities	$ 419	$ 456	$ 534	$ 529

Revenues (Changes) (Details)

Revenues (Changes) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Significant changes to contract liabilities
Total contract liabilities, at beginning of period	$ 456	$ 529
Decrease due to recognition of revenues for goods and services	(44)	(41)
Increase due to goods and services transferred over time	7	46
Total contract liabilities, at end of period	$ 419	$ 534

Drilling Fleet (Details)

Drilling Fleet (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Changes in construction work in progress, including capital expenditures and other capital additions, such as capitalized interest
Total capital expenditures	$ 59	$ 107
Construction in Progress
Changes in construction work in progress, including capital expenditures and other capital additions, such as capitalized interest
Construction work in progress, at beginning of period	828	753
Total capital expenditures	59	107
Changes in accrued capital additions	(7)	(24)
Property and equipment placed into service	(14)	(62)
Construction work in progress, at end of period	866	774
New builds
Changes in construction work in progress, including capital expenditures and other capital additions, such as capitalized interest
Total capital expenditures	45	50
Other equipment and construction projects
Changes in construction work in progress, including capital expenditures and other capital additions, such as capitalized interest
Total capital expenditures	$ 14	$ 57

Drilling Fleet (Impairment held

Drilling Fleet (Impairment held and used) (Details) $ / shares in Units, $ in Millions	3 Months Ended
	Mar. 31, 2020USD ($)$ / shares
Impairment of assets held and used
Loss associated with impairment, net of tax (per share) | $ / shares	$ 0.23
Midwater floaters
Impairment of assets held and used
Impairment of in use assets | $	$ 31
Loss associated with impairment, net of tax (per share) | $ / shares	$ 0.05
Loss associated with in use asset impairment, tax effect | $	$ 0

Drilling Fleet (Impairment he_2

Drilling Fleet (Impairment held for sale) (Details) $ / shares in Units, $ in Millions	3 Months Ended
	Mar. 31, 2020USD ($)$ / shares
Drilling Fleet
Aggregate loss on impairment of assets held for sale	$ 137
Aggregate loss on impairment of assets held for sale, net of tax	$ 136
Loss associated with impairment, net of tax (per share) | $ / shares	$ 0.23

Drilling Fleet (Disposal) (Deta

Drilling Fleet (Disposal) (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Dispositions
Net cash proceeds from sale of assets	$ 6	$ 1
Gain (loss) on the sale of assets	(59)	$ (1)
Assets sold, not discontinued operations | Rig sales
Dispositions
Net cash proceeds from sale of assets	4
Gain (loss) on the sale of assets	$ (60)
Gain (loss) on the sale of assets per diluted share	$ (0.10)
Gain (loss) on disposal of assets, tax effect	$ 0

Debt (Details)

Debt (Details) - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
Principal amount
Total installments of debt	$ 7,249	$ 7,376
Debt due within one year	461	449
Long-term debt	6,788	6,927
Carrying amount
Total debt	7,620	7,807
Debt due within one year	524	505
Long-term debt	7,096	7,302
6.375% Senior Notes due December 2021
Principal amount
Total installments of debt	38	38
Debt due within one year	38	38
Carrying amount
Total debt	$ 38	38
Debt instrument interest rate stated percentage	6.375%
5.52% Senior Secured Notes due May 2022
Principal amount
Total installments of debt	$ 89	111
Debt due within one year	71	93
Carrying amount
Total debt	88	111
Debt due within one year	$ 70	92
Debt instrument interest rate stated percentage	5.52%
3.80% Senior Notes due October 2022
Principal amount
Total installments of debt	$ 27	27
Carrying amount
Total debt	$ 27	27
Debt instrument interest rate stated percentage	3.80%
0.50% Exchangeable Senior Bonds due January 2023
Principal amount
Total installments of debt	$ 140	463
Carrying amount
Total debt	$ 139	462
Debt instrument interest rate stated percentage	0.50%
5.375% Senior Secured Notes due May 2023
Principal amount
Total installments of debt	$ 362	364
Debt due within one year	47	47
Carrying amount
Total debt	359	360
Debt due within one year	$ 46	46
Debt instrument interest rate stated percentage	5.375%
5.875% Senior Secured Notes due January 2024
Principal amount
Total installments of debt	$ 544	585
Debt due within one year	83	83
Carrying amount
Total debt	536	577
Debt due within one year	$ 80	80
Debt instrument interest rate stated percentage	5.875%
7.75% Senior Secured Notes due October 2024
Principal amount
Total installments of debt	$ 360	360
Debt due within one year	60	60
Carrying amount
Total debt	354	354
Debt due within one year	$ 58	58
Debt instrument interest rate stated percentage	7.75%
6.25% Senior Secured Notes due December 2024
Principal amount
Total installments of debt	$ 375	375
Debt due within one year	62	62
Carrying amount
Total debt	370	369
Debt due within one year	$ 60	60
Debt instrument interest rate stated percentage	6.25%
4.00% Senior Guaranteed Exchangeable Bonds due December 2025
Principal amount
Total installments of debt	$ 294
Carrying amount
Total debt	$ 260
Debt instrument interest rate stated percentage	4.00%
6.125% Senior Secured Notes due August 2025
Principal amount
Total installments of debt	$ 435	468
Debt due within one year	66	66
Carrying amount
Total debt	428	461
Debt due within one year	$ 64	64
Debt instrument interest rate stated percentage	6.125%
7.25% Senior Notes due November 2025
Principal amount
Total installments of debt	$ 411	411
Carrying amount
Total debt	$ 406	405
Debt instrument interest rate stated percentage	7.25%
7.50% Senior Notes due January 2026
Principal amount
Total installments of debt	$ 569	569
Carrying amount
Total debt	$ 565	565
Debt instrument interest rate stated percentage	7.50%
2.50% Senior Guaranteed Exchangeable Bonds due January 2027
Principal amount
Total installments of debt	$ 238	238
Carrying amount
Total debt	274	277
Debt due within one year	$ 6	6
Debt instrument interest rate stated percentage	2.50%
11.50% Senior Guaranteed Notes due January 2027
Principal amount
Total installments of debt	$ 687	687
Carrying amount
Total debt	1,113	1,139
Debt due within one year	$ 70	61
Debt instrument interest rate stated percentage	11.50%
6.875% Senior Secured Notes due February 2027
Principal amount
Total installments of debt	$ 550	550
Debt due within one year	34
Carrying amount
Total debt	543	542
Debt due within one year	$ 32
Debt instrument interest rate stated percentage	6.875%
8.00% Senior Notes due February 2027
Principal amount
Total installments of debt	$ 612	612
Carrying amount
Total debt	$ 607	606
Debt instrument interest rate stated percentage	8.00%
7.45% Notes due April 2027
Principal amount
Total installments of debt	$ 52	52
Carrying amount
Total debt	$ 51	51
Debt instrument interest rate stated percentage	7.45%
8.00% Debentures due April 2027
Principal amount
Total installments of debt	$ 22	22
Carrying amount
Total debt	$ 22	22
Debt instrument interest rate stated percentage	8.00%
7.00% Notes due June 2028
Principal amount
Total installments of debt	$ 261	261
Carrying amount
Total debt	$ 265	266
Debt instrument interest rate stated percentage	7.00%
7.50% Notes due April 2031
Principal amount
Total installments of debt	$ 396	396
Carrying amount
Total debt	$ 394	394
Debt instrument interest rate stated percentage	7.50%
6.80% Senior Notes due March 2038
Principal amount
Total installments of debt	$ 610	610
Carrying amount
Total debt	$ 605	605
Debt instrument interest rate stated percentage	6.80%
7.35% Senior Notes due December 2041
Principal amount
Total installments of debt	$ 177	177
Carrying amount
Total debt	$ 176	$ 176
Debt instrument interest rate stated percentage	7.35%

Debt (Maturities) (Details)

Debt (Maturities) (Details) - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
Scheduled maturities of debt
Total installments of debt	$ 7,249	$ 7,376
Total Installments
Scheduled maturities of debt
2022	537
2023	664
2024	972
2025	593
2026	1,605
Thereafter	3,340
Total installments of debt	7,711
Total debt-related balances, net	(91)
Total carrying amount of debt	7,620
Principal installments
Scheduled maturities of debt
2022	461
2023	588
2024	895
2025	516
2026	1,527
Thereafter	3,262
Total installments of debt	7,249
Other installments
Scheduled maturities of debt
2022	76
2023	76
2024	77
2025	77
2026	78
Thereafter	78
Total installments of debt	$ 462

Debt (Interest and Facility) (D

Debt (Interest and Facility) (Details) $ in Millions	3 Months Ended
	Mar. 31, 2021USD ($)
6.375% Senior Notes due December 2021
Debt
Debt instrument interest rate stated percentage	6.375%
Interest rate, as adjusted (as a percent)	8.375%
3.80% Senior Notes due October 2022
Debt
Debt instrument interest rate stated percentage	3.80%
Interest rate, as adjusted (as a percent)	5.80%
7.35% Senior Notes due December 2041
Debt
Debt instrument interest rate stated percentage	7.35%
Interest rate, as adjusted (as a percent)	9.35%
Five-Year Revolving Credit Facility
Debt
Borrowing capacity, maximum	$ 1,300
Commitment fee percentage at period end	0.875%
Credit facility amount outstanding	$ 0
Letters of credit issued and outstanding	25
Credit facility available borrowing capacity	$ 1,300
Five-Year Revolving Credit Facility | Minimum
Debt
Commitment fee percentage at period end	0.375%
Five-Year Revolving Credit Facility | Maximum
Debt
Commitment fee percentage at period end	1.00%
Five-Year Revolving Credit Facility | Adjusted LIBOR
Debt
Spread on variable rate basis (as a percent)	3.375%
Percentage reduction to the calculated variable rate	1.00%
Five-Year Revolving Credit Facility | Adjusted LIBOR | Minimum
Debt
Spread on variable rate basis (as a percent)	2.625%
Five-Year Revolving Credit Facility | Adjusted LIBOR | Maximum
Debt
Spread on variable rate basis (as a percent)	3.375%

Debt (Exchange and Issue) (Deta

Debt (Exchange and Issue) (Details) $ / shares in Units, $ in Millions	Feb. 26, 2021USD ($)$ / shares	Jan. 17, 2020USD ($)	Mar. 31, 2021USD ($)$ / shares	Mar. 31, 2020USD ($)	Dec. 31, 2020USD ($)
Debt
Issuance of debt in exchange transactions			$ 294
Aggregate cash payment			12	$ 813
Proceeds from issuance of debt				$ 743
Exchanged
Debt
Issuance of debt in exchange transactions			294
Aggregate cash payment			$ 11
0.50% Exchangeable Senior Bonds due January 2023
Debt
Debt conversion ratio			0.09729756
Debt conversion (in dollars per share) | $ / shares			$ 10.28
Effective interest rate (as a percent)			0.50%
Fair value of debt			$ 104
Equity component of convertible debt instruments			$ 172		$ 172
Aggregate cash payment	$ 11
Original debt in exchange	323
Gains (losses) on restructuring	$ 51
Gains (losses) on restructuring (in dollars per share) | $ / shares	$ 0.08
4.00% Senior Guaranteed Exchangeable Bonds due December 2025
Debt
Debt conversion ratio			0.19047620
Debt conversion (in dollars per share) | $ / shares			$ 5.25
Effective interest rate (as a percent)			6.90%
Fair value of debt			$ 280
Equity component of convertible debt instruments	$ 260
Issuance of debt in exchange transactions	$ 294
2.50% Senior Guaranteed Exchangeable Bonds due January 2027
Debt
Debt conversion ratio			0.16216260
Debt conversion (in dollars per share) | $ / shares			$ 6.17
Effective interest rate (as a percent)			0.00%
Fair value of debt			$ 195
8.00% Senior Notes due February 2027
Debt
Debt instrument face value		$ 750
Proceeds from issuance of debt		$ 743
Redemption price of debt instrument (as a percent)		100.00%

Debt (Settled) (Details)

Debt (Settled) (Details) - USD ($) $ in Millions	Feb. 26, 2021	Mar. 31, 2021	Mar. 31, 2020
Debt
Debt retirement		$ 324	$ 769
Aggregate cash payment		12	813
Aggregate principal amount of debt issued in exchanges		294
Aggregate net gain (loss)		$ 51	(57)
6.50% Senior Notes due November 2020
Debt
Debt instrument interest rate stated percentage		6.50%
Debt retirement			8
6.375% Senior Notes due December 2021
Debt
Debt instrument interest rate stated percentage		6.375%
Debt retirement			38
3.80% Senior Notes due October 2022
Debt
Debt instrument interest rate stated percentage		3.80%
Debt retirement			3
0.50% Exchangeable Senior Bonds due January 2023
Debt
Debt instrument interest rate stated percentage		0.50%
Debt retirement		$ 323
Aggregate cash payment	$ 11
5.375% Senior Secured Notes due May 2023
Debt
Debt instrument interest rate stated percentage		5.375%
Debt retirement		$ 1	6
9.00% Senior Notes due July 2023
Debt
Debt instrument interest rate stated percentage		9.00%
Debt retirement			714
Redeemed
Debt
Debt retirement			714
Aggregate cash payment			767
Aggregate net gain (loss)			(65)
Redeemed | 9.00% Senior Notes due July 2023
Debt
Debt retirement			714
Repurchased
Debt
Debt retirement		$ 1	55
Aggregate cash payment		1	46
Aggregate net gain (loss)			8
Repurchased | 6.50% Senior Notes due November 2020
Debt
Debt retirement			8
Repurchased | 6.375% Senior Notes due December 2021
Debt
Debt retirement			38
Repurchased | 3.80% Senior Notes due October 2022
Debt
Debt retirement			3
Repurchased | 5.375% Senior Secured Notes due May 2023
Debt
Debt retirement		1	$ 6
Exchanged
Debt
Debt retirement		323
Aggregate cash payment		11
Aggregate principal amount of debt issued in exchanges		294
Aggregate net gain (loss)		51
Exchanged | 0.50% Exchangeable Senior Bonds due January 2023
Debt
Debt retirement		$ 323

Income Taxes (Provision) (Detai

Income Taxes (Provision) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Income Taxes
Effective tax rate	17.80%	1.10%
Income tax benefit	$ (21)	$ (4)
Various discrete tax items expense (benefit)	$ (27)	$ (20)
Annual effective tax rate excluding discrete items (as a percent)	(5.70%)	(9.50%)

Income Taxes (Tax Returns) (Det

Income Taxes (Tax Returns) (Details) - Brazil R$ in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2021BRL (R$)	Mar. 31, 2021USD ($)	Mar. 31, 2020BRL (R$)	Mar. 31, 2020USD ($)
Corporate income tax
Income Tax Examination
Net adjustments of additional taxes, including interest and penalties	R$ 641	$ 114
Indirect tax
Income Tax Examination
Net adjustments of additional taxes, including interest and penalties			R$ 96	$ 17

Loss Per Share (Details)

Loss Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Numerator for loss per share, basic and diluted
Net loss attributable to controlling interest	$ (99)	$ (392)
Denominator for loss per share, basic and diluted
Weighted-average shares outstanding (in shares)	616,000	613,000
Effect of share-based awards (in shares)	1,000	1,000
Weighted-average shares for per share calculation	617,000	614,000
Loss per share, basic and diluted (in dollars per share)	$ (0.16)	$ (0.64)
Share-based awards
Denominator for loss per share, basic and diluted
Securities excluded from earnings per share calculation (in shares)	13,800	11,100
Convertible debt
Denominator for loss per share, basic and diluted
Securities excluded from earnings per share calculation (in shares)	92,900	84,000
0.50% Exchangeable Senior Bonds due January 2023
Denominator for loss per share, basic and diluted
Debt instrument interest rate stated percentage	0.50%
2.50% Senior Guaranteed Exchangeable Bonds due January 2027
Denominator for loss per share, basic and diluted
Debt instrument interest rate stated percentage	2.50%
4.00% Senior Guaranteed Exchangeable Bonds due December 2025
Denominator for loss per share, basic and diluted
Debt instrument interest rate stated percentage	4.00%

Contingencies (Details)

Contingencies (Details) - Asbestos litigation	Mar. 31, 2021plaintifflawsuit
Contingencies
Number of claims | lawsuit	256
LA
Contingencies
Number of claims	9
Illinois and Missouri
Contingencies
Number of claims	14

Financial Instruments (Details)

Financial Instruments (Details) - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
Financial instruments
Long-term debt, including current maturities	$ 7,620	$ 7,807
Carrying amount
Financial instruments
Cash and cash equivalents	1,066	1,154
Restricted cash and cash equivalents	388	406
Long-term debt, including current maturities	7,620	7,807
Fair value
Financial instruments
Cash and cash equivalents	1,066	1,154
Restricted cash and cash equivalents	388	406
Long-term debt, including current maturities	$ 5,503	$ 4,820